Abstract : This introduction addresses the two last centuries before the advent of Islam through two questions: is the decline observed in the Arabian Peninsula to be regarded as a local phenomenon or as part of a regional process? Shall we consider the period of transition from Pre-Islamic to Islamic time as a break in continuity or not? I will first consider the recent studies devoted to the decline of the Arabian Peninsula from the 4th to the 6th century. I will then turn to the Near East so as to determine whether the process observed in Arabia was a local one or an epiphenomenon of a larger crisis. Putting forward different situations with different causes, it emerges that no global decline can be postulated in this region on the eve of Islam. As a consequence, and taking into account the origin of the Arab Islamic culture, the last part of this paper points out that the transition to the Islamic era was a progressive and long-lasting change rather than a break.